As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. When you push the platform, you compress the springs. You do an amount of work of 79.0 J when you compress the springs a distance of 0.190 m from their uncompressed length.(a) What magnitude of force must you apply to hold the platform in this position?

Answers

Answer 1

Explanation:

The given data is as follows.

         Work done by the force, (W) = 79.0 J

         Compression in length (x) = 0.190 m

So, formula for parallel combination of springs  equivalent is as follows.

           [tex]k_{eq} = K_{1} + K_{2}[/tex]

                    = 2k

Hence, work done is as follows.

             W = [tex]\frac{1}{2}k_{eq} \times x^{2}[/tex]

           [tex]k_{eq} = \frac{2W}{x^{2}}[/tex]

                       = [tex]\frac{2 \times 79}{(0.19)^{2}}[/tex]

                       = [tex]\frac{158}{0.0361}[/tex]

                       = 4376.73 N/m

Hence, magnitude of force required to hold the platform is as follows.

               F = [tex]k_{eq}x[/tex]

                  = [tex]4376.73 N/m \times 0.19 m[/tex]

                  = 831.58 N

Thus, we can conclude that magnitude of force you must apply to hold the platform in this position is 831.58 N.


Related Questions

A projectile is launched with a launch angle of 55° with respect to the horizontal direction and with initial speed 78 m/s. How long does it remain in flight?

Answers

Answer:

The projectile is in air for 13.03 seconds.

Explanation:

Given that,

Angle of projection of the projectile, [tex]\theta=55^{\circ}[/tex]

Initial speed of the projectile, u = 78 m/s

To find,

We need to find the time of flight of the projectile.

Solution,

It is defined as the time taken by the projectile when it is in air. It is given by the formula as :

[tex]T=\dfrac{2u\ \sin\theta}{g}[/tex]

[tex]T=\dfrac{2\times 78\ \sin(55)}{9.8}[/tex]

T = 13.03 seconds

So, the projectile is in air for 13.03 seconds.

A piece of Nichrome wire has a radius of 6.5 104 m. It is used in a laboratory to make a heater that uses 4.00 102 W of power when connected to a voltage source of 120 V. Ignoring the effect of temperature on resistance, estimate the necessary length of wire.

Answers

Answer:

[tex]L=4.8*10^{17}m[/tex]

Explanation:

Given data

Power P=4.00×10²W

Radius r=6.5×10⁴m

Voltage V=120V

To find

Length of wire L

Solution

We know that resistance of wire can be obtained from

[tex]P=\frac{V_{2}}{R}\\ R=\frac{V_{2}}{P}[/tex]

We also know that R=pL/A solving the length noting that A=πr²

and using p=100×10⁻⁸Ω.m we find that

So

[tex]L=\frac{RA}{p}\\ L=\frac{\frac{(V^{2})}{P}(\pi r^{2}) }{p} \\L=\frac{V^{2}(\pi r^{2})}{pP}\\ L=\frac{(120V)^{2}\pi (6.5*10^{4} m)^{2} }{100*10^{-8}(4.00*10^{2} W) }\\ L=4.8*10^{17}m[/tex]

Final answer:

To calculate the length of Nichrome wire needed for a heating element using 400 W at 120 V, one determines the resistance and then uses it with the wire's cross-sectional area and resistivity. Approximately 41.45 meters of wire is required.

Explanation:

To estimate the necessary length of Nichrome wire for a laboratory heater, we start by calculating the resistance using the power and voltage supplied. The formula for power (P) in terms of voltage (V) and resistance (R) is P = V2 / R. Given P = 400 W and V = 120 V, the resistance can be calculated as follows:

R = V2 / P = (1202) / 400 = 36 Ω.

Next, we use the resistivity (ρ) of Nichrome and the cross-sectional area (A) of the wire to find the length (L). The formula R = ρL / A is applicable here, where ρ for Nichrome is approximately 1.10×10-6 Ω·m and A = πr2. The radius (r) given is 6.5×10-4 m, so:

A = π(6.5×10-4)2 = 1.33×10-6 m2.

Substituting the values into the formula, we get:

L = (R · A) / ρ = (36 · 1.33×10-6) / (1.10×10-6) ≠ 41.45 m.

Thus, approximately 41.45 meters of Nichrome wire is required for the heater to use 400 W of power at 120 V.

What is Pascal's Law? When gasses aren't constrained they tend to expand or contract, which depends on the pressure. You can squeeze air into tighter spaces by pressing the molecules together. In a contained incompressible fluid, any external pressure applied at one point will raise pressure equally at every point. An object placed in water is buoyed up with a force equal to the weight of the fluid the object displaces.

Answers

Answer: In a contained incompressible fluid, any external pressure applied at one point will raise pressure equally at every point.

Explanation: This law was put forward by Blaise Pascal, a French mathematician in 1648. Pascal's Law states that in a contained incompressible fluid, any external pressure applied at one point will raise pressure equally at every point. Pascal's law has been used in fluid mechanics for different applications these includes:

- the hydraulic jack used in automobile listings,

- most automobile braking systems,

-water towers, and dams.

A beam of protons is accelerated through a potential difference of 0.750 kVkV and then enters a uniform magnetic field traveling perpendicular to the field. You may want to review (Pages 641 - 643) . For related problem-solving tips and strategies, you may want to view a Video Tutor Solution of electron motion in a microwave oven. Part A What magnitude of field is needed to bend these protons in a circular arc of diameter 1.80 mm ? Express your answer in tesla to three significant figures. BpBp = nothing TT SubmitRequest Answer Part B What magnetic field would be needed to produce a path with the same diameter if the particles were electrons having the same speed as the protons? Express your answer in tesla to three significant figures. BeBe = nothing TT SubmitRequest Answer

Answers

Answer:

Explanation:

A force is provided by the magnetic field which perpendicular to both the velocity of the charge and magnetic field

F = qvB  where B is the magnetic field in tesla, q is charge and v is velocity

The potential energy is transferred into kinetic energy

PE = Vq = 1/2 mv²

v = √(2Vq/ m)

charge on the proton = 1.602 × 10 ⁻¹⁹ C and mass of a proton = 1.673 × 10⁻²⁷

v = √ (( 2 × 1.602 × 10 ⁻¹⁹ C × 0.75 × 10³V ) / (1.673 × 10⁻²⁷)) = √( 1.4363 × 10¹¹ ) = 3.79 × 10⁵ m/s

The force of magnetic field produces centripetal force

qvB = mv² /R

where  R radius = 1.80mm = 0.0018 m / 2 = 0.0009 m

qvB = ( m / R ) × (2qV /m)

cancel the common terms

vB = 2V / R

3.79 × 10⁵ m/s × B = 2 × 0.75 × 10³V / 0.0009 = 1.667 × 10⁶

B = 1.667 × 10⁶ / 3.79 × 10⁵ m/s = 4.40 T

b) magnetic field needed for the electron

qvB = mv² /R where m is the mass of an electron = 9.11 × 10⁻³¹ Kg

qB = mv/R

qB = ( 9.11 × 10⁻³¹ Kg × 3.79 × 10⁵ m/s) / 0.0009

qB  = 3.8363 × 10 ⁻²²

B = 3.8363 × 10 ⁻²² / 1.602 × 10⁻¹⁹ kg = 0.0239 T

There has long been an interest in using the vast quantities of thermal energy in the oceans to run heat engines. A heat engine needs a temperature difference, a hot side and a cold side. Conveniently, the ocean surface waters are warmer than the deep ocean waters. Suppose you build a floating power plant in the tropics where the surface water temperature is ≈≈ 30 ∘C∘C. This would be the hot reservoir of the engine. For the cold reservoir, water would be pumped up from the ocean bottom where it is always ≈≈ 5 ∘C∘C.What is the maximum possible efficiency of such a power plant? In%.

Answers

Answer:

[tex]\eta_{th} = 8.247\%[/tex]

Explanation:

The maximum possible efficiency for the floating power plant is given by the Carnot's Efficiency:

[tex]\eta_{th} = \left(1-\frac{278.15\,K}{303.15\,K} \right)\times 100\%[/tex]

[tex]\eta_{th} = 8.247\%[/tex]

An inventor claims to have devised a cyclical engine for use in space vehicles that operates with a nuclear-fuelgenerated energy source whose temperature is 920 R and a sink at 490 R that radiates waste heat to deep space. He also claims that this engine produces 4.5 hp while rejecting heat at a rate of 15,000 Btu/h. Is this claim valid?

Answers

Answer:

Valid

Explanation:

to determine if the claim is valid, we compare the efficiency of the device to that of a Carnot engine.

The following data were given

High Temperature = 920R,

Low temperature =490R

work=4.5hp =4.5*2544.5=11450.25Btu/h

low heat Ql heat= 15000Btu/h

High heat Qh=work +Ql=11450.25Btu/h+15000Btu/h=26450.25Btu/h

Next we cal calculate the efficiency of the Carnot engine

[tex]E_Carnot=1-\frac{T_L}{T_H}\\ E_Carnot=1-\frac{490}{920}\\ E_Carnot=0.467[/tex]

Hence the maximum efficiency at the given temperature is 47%

Next we calculate the efficiency of the device

[tex]E_device=\frac{work}{Q_H} \\E_device=\frac{11450.25}{26450.25} \\E_device=0.433\\[/tex]

which is 43%

since the maximum efficiency of 47% is not exceeded, we can conclude that the claim is valid

A 925 kg car rounds an unbanked curve at a speed of 25 m/s. If the radius of the curve is 72, what is the minimum coefficient of friction between the car and the road required so that the car does not skid?

Answers

Answer:

[tex]\mu_s^{min}=0.885[/tex]

Explanation:

The centripetal force is provided by the static friction between the car and the road, and always have to comply with [tex]f\leq\mu_sN[/tex], so we have:

[tex]ma_{cp}=f\leq\mu_sN=\mu_smg[/tex]

Which means:

[tex]a_{cp}=\frac{v^2}{r}\leq\mu_sg[/tex]

So we have:

[tex]\frac{v^2}{gr}\leq\mu_s[/tex]

Which means that [tex]\frac{v^2}{gr}[/tex] is the minimum value the coefficient of static friction can have, which for our values is:

[tex]\mu_s^{min}=\frac{v^2}{gr}=\frac{(25m/s)^2}{(9.81m/s^2)(72m)}=0.885[/tex]

Final answer:

To keep the car from skidding, the frictional force between the car and the road must provide the necessary centripetal force to keep the car moving in a circle. The minimum coefficient of friction required would be about 0.86.

Explanation:

To determine this, we must understand that the friction force between the car and the road surface is what keeps the car in a curved path. If the speed of the car or the radius of the curve is too large, a greater force is needed to keep the car from skidding. This force must be supplied as an increased friction force, which implies a larger coefficient of friction.

The centripetal force needed to keep a car on the road as it rounds a turn is provided by the frictional force between the road and the car's tires. We can use the formula for centripetal force where Fc=m*v^2/r. Here, Fc is the centripetal force, m is the mass of the car, v is the speed of the car, and r is the radius of the curve. In this case, friction provides the centripetal force, so Fc is also equal to the force of static friction, which is less than or equal to the coefficient of static friction times the normal force (µ*m*g).

Setting these equal and solving for µ gives µ=v^2/(g*r). Plugging in the given values (v=25 m/s, g=9.8 m^2/s, and r=72 m), we find that the minimum coefficient of friction required is about 0.86. This is reasonable; a typical car with good tires on dry concrete requires a minimum coefficient of friction of about 0.7 to keep from skidding in a curve.

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An RLC circuit with a resistor of R\:=\:1 R = 1 k, capacitor ofC\:=\:3 C = 3 F, and inductor ofL\:=\:2 L = 2 H reaches a maximum current through the inductor of 7 mA. When all of the energy stored in the circuit is in the inductor, what is the magnetic energy stored? (Express your answer in micro-Joules) In the same circuit explained above, if all the energy is then transferred into the capacitor, what voltage drop will there be across the capacitor? (Express your answer in Volts to the hundredths place)

Answers

Answer:

Magnetic energy stored in the inductor when all of the energy in the circuit is in the inductor = 0.049 mJ

If all the energy is then transferred into the capacitor, the voltage drop across the capacitor = 0.00572 V = 0.01 V (expressed to the hundredths value)

Explanation:

In an RLC circuit with maximum current of 7mA = 0.007 A

When all of the energy is stored in the inductor, maximum current will flow through it,

Hence E = (1/2) LI²

L = inductance of the inductor = 2 H

E = (1/2) (2)(0.007²) = 0.000049 J = 0.049 mJ

When all the energy in the circuit is in the capacitor, this energy will be equal to the energy calculated above.

And for a capacitor, energy is given as

E = (1/2) CV²

E = 0.000049 J, C = 3 F, V = ?

0.000049 = (1/2)(3)(V²)

V = 0.00572 V = 0.01 V

Suppose Person A is traveling on a spaceship going 50% of the speed of light. Person A measures the length of the spaceship to be 10 meters. How long would a Person B measure the spaceship if person B were on a planet as the spaceship passed by?

Answers

Answer:

L = 8.66 m

Explanation:

The length measured by the moving observer is related to the true length is given by

L = L₀ √1 - (v²/c²)

Where L₀ is the length of the spaceship as measured by person A, v is the speed of spaceship of person A and c is the speed of light c = 3.8x10ᵃ m/s

L = 10√1 - (0.5c)²/c²

L = 10√1 - (0.5*3.8x10ᵃ)²/3.8x10ᵃ ²

L = 8.66 m

Therefore, the Person B would measure the spaceship length to be 8.66 m

In a game of baseball, a player hits a high fly ball to the outfield. (a) Is there a point during the flight of the ball where its velocity is parallel to its acceleration? (b) Is there a point where the ball’s velocity is perpendicular to its acceleration? Explain in each case.

Answers

Final answer:

The velocity and acceleration vectors of a baseball can change during its flight. At the ball's maximum height, its velocity is parallel to its acceleration. There is no point where the ball's velocity is perpendicular to its acceleration.

Explanation:

In a game of baseball, the velocity and acceleration of a ball can change as it moves through the air. (a) Yes, there is a point during the flight of the ball where its velocity is parallel to its acceleration. This occurs when the ball reaches its maximum height. At this point, the ball stops moving upward and starts moving downward. Both the velocity and acceleration vectors are directed downward and therefore parallel to each other.

(b) No, there is no point during the flight of the ball where its velocity is perpendicular to its acceleration. The orientation of the velocity and acceleration vectors will always be either parallel or antiparallel to each other.

A polarized light is incident on several polarizing disks whose planes are parallel and centered on common axis. Suppose that the transmission axis of the first polarizer is rotated 20° relative to the axis of polarization of the incident light, and that the transmission axis of each additional analyzer is rotated 20° relative to the transmission axis of the previous one. What is the maximum number of polarizer needed (whole number), so the transmitted light through all polarizing sheets has an intensity that is equal at least 12% that striking the first polarizer?

Answers

Answer:

The number of polarizer needed so transmitted light has at least 12% intensity = 17

Explanation:

Given :

Angle between incident light and optic axis of polarizer = 20°

Given that, the transmission axis of each additional analyzer is rotated 20° relative to the transmission axis of the previous one

According to the malus law,

The intensity of the transmitted light passes through the polarizer is proportional to the square of the cosine of angle between the transmission axis to the optic axis.

⇒  [tex]I = I_{o} cos^{2} \alpha[/tex]

Where, [tex]I =[/tex] transmitted intensity through polarizer, [tex]I_{o} =[/tex] incident intensity of the light.

Given in question, all the time [tex]\alpha =[/tex] 20°

By calculation ∴ [tex]cos^{2} 20 = 0.883[/tex]

After 1st polarizer,

∴ [tex]I_{1} = 0.883I_{o}[/tex]

Now we need to multiply all the time 0.883 until we get 0.12 (relative 20° angle given in question)

After 17th polarizer we get 0.1205 ≅ 0.12

[tex]I_{17} = 0.883^{17} = 0.1205 \times 100 = 12[/tex]% [tex]I_{o}[/tex]

Means we get 12% intensity after 17th polarizing disk.

Choose the correct statement: Group of answer choices A proton tends to go from a region of low potential to a region of high potential. The potential of a negatively charged conductor must be negative. None of the other responses is correct. If V

Answers

Answer:

TRUE. The potential of a negatively charged conductor must be negative

Explanation:

Let's examine each statement

The positively charged proton moves in the direction of the electric field, the power and the electric field are related

                ΔU = - E ds

                [tex]U_{f}[/tex] - U₀ = - E ds

                E = (U₀ –U_{f}) / s

To have a positive electric field the initial potential must be greater than the final potential, so the proton moves from a greater potential to a smaller one.

This statement is FALSE

The second statement

The potential has the same sign as the elective charge.

This statement is TRUE

A proton tends to move to a region of higher potential is False, while The potential of a negatively charged conductor must be negative is True.

Electric Potential:

The proton is a positively charged particle and moves in the direction of the electric field lines.

In the case of a positive charge, the electric field lines are away from the charge, which will push the proton away.

We know that the potential is inversely proportional to distance.

Thus, as the proton moves away, it is going from a higher potential to a lower potential.

The same can be proven in the case of an electric field generated by a negative charge, by using proper sign convention.

So the statement that a proton tends to go from a region of low potential to a region of high potential is FALSE

The potential has the same sign as the electric charge.

So the statement that the potential of a negatively charged conductor must be negative is TRUE

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The radius of Venus (from the center to just above the atmosphere) is 6050 km (6050✕103 m), and its mass is 4.9✕1024 kg. An object is launched straight up from just above the atmosphere of Venus. (a) What initial speed is needed so that when the object is far from Venus its final speed is 8000 m/s? vinitial = m/s (b) What initial speed is needed so that when the object is far from Venus its final speed is 0 m/s? (This is called the "escape speed.") vescape = m/s

Answers

Answer:

(a) The initial speed required is 13116 m/s

(b) The escape speed is 10394 m/s

This problem involves the application of newtons laws of gravitation. The forces in action here are conservative and as a result mechanical energy is conserved.

The full calculation can be found in the attachment below.

Explanation:

In both parts (a) and (b) the energy conservation equation were used. Assumption was made that when the object is very far from the planet the distance from the planet's center approaches infinity and the gravitational potential energy approaches zero.

The calculation can be found below.

A 1.50-V battery supplies 0.204 W of power to a small flashlight. If the battery moves 8.33 1020 electrons between its terminals during the time the flashlight is in operation, how long was the flashlight used

Answers

Answer:

981.41 secs

Explanation:

Parameters given:

Voltage, V = 1.5V

Power, P = 0.204W

Number of electrons, n = 8.33 * 10^20

First, we calculate the current:

P = I*V

I = P/V

I = 0.204/1.5 = 0.136A

The total charge of 8.33 * 10^20 electrons is:

Q = 8.33 * 10^20 * 1.6023 * 10^(-19)

Q = 133.47 C

Current, I, is given as:

I = Q/t

=> t = Q/I

t = 133.47/0.136 = 981.41 secs

In physics, power is calculated using the formula P = IV, where P is power, I is current, and V is voltage. By applying this formula, along with the relationship between charge, current, and time, the time the flashlight was used can be calculated.

Power is determined by the rate at which energy is transferred, calculated as P = IV where P is power, I is current, and V is voltage. In this scenario, the power supplied is 0.204 W from a 1.50-V battery. The formula P = IV can be rearranged to find the current flowing, which is 0.136 A.

To determine the time the flashlight was used, we can utilize the relationship between charge, current, and time: Q = It. Given 8.33 x 10^20 electrons moved, we need to convert this to Coulombs by recognizing that 1 electron has a charge of approximately 1.6 x 10^-19 C. By dividing the total charge by the current, we find the time t to be approximately 1.23 x 10^19 seconds.

You are testing a new amusement park roller coaster with an empty car with a mass of 120 kg. One part of the track is a vertical loop with a radius of 12.0 m. At the bottom of the loop (point A) the car has a speed of 25.0 m/s and at the top of the loop (point B) it has speed of 8.00 m/s. As the car rolls from point A to point B, how much work is done by friction?

Answers

Answer:

[tex]W_f=-62460\ J[/tex]

Explanation:

Given that

mass of the car ,m = 120 kg

Radius ,R= 12 m

Speed at the bottom , u = 25 m/s

Speed at top ,v= 8 m/s

We know that

Work done by all the forces = Change in the kinetic energy

Work done by gravity +  Work done by friction =Change in the kinetic energy

By taking point A as reference

[tex]m g \times (2R) + W_f=\dfrac{1}{2}mv^2-\dfrac{1}{2}mu^2[/tex]

Now by putting the values in the above equation we get

[tex]120\times 10\times 2\times 12+ W_f=\dfrac{1}{2}\times 120\times 8^2-\dfrac{1}{2}\times 120\times 25^2[/tex]

[tex]W_f=\dfrac{1}{2}\times 120\times 8^2-\dfrac{1}{2}\times 120\times 25^2-120\times 10\times 2\times 12\ J[/tex]

[tex]W_f=-62460\ J[/tex]

Therefore the work done by friction force will be -62460 J.

Consider a platinum wire (σ= 1.0 × 107 Ω-1·m-1) with a cross-sectional area of 1 mm2 (similar to your connecting wires) and carrying 0.3 amperes of current, which is about what you get in a circuit with a round bulb and two batteries in series. Calculate the strength of the very small electric field required to drive this current through the wire.

Answers

Answer: 0.03 N/C

Explanation:

We use the current density formula to solve this question.

I/A = σ * E

Where,

I = current flowing in the circuit = 0.3 A

A = cross sectional area of the wire = 1 mm²

σ = resistivity of the wire = 1*10^7 Ω^-1·m^-1

E = strength of the electric field required

I/A = σ *E

E = I/(A * σ)

First we convert area from mm to m, so that, 1*10^-3 mm = 1*10^-6 m

E = 0.3 A / (1*10^-6 m * 1*10^7 Ω^-1·m^-1)

E = 0.3 A / 10 Ω^-1

E = 0.03 N/C

The required electric field to drive given current through the wire is 0.03 V/m.

To calculate the strength of the electric field required to drive a current of 0.3 amperes through a platinum wire, we can use the relationship between current density, electrical conductivity, and electric field.

The current density (J) is given by:

J = I / A

where I = 0.3 A and A = 1 mm² = 1 × 10⁻⁶ m².

Substituting the values, we get:

J = 0.3 A / (1 × 10⁻⁶ m²) = 3 × 10⁵A/m²

Next, we use Ohm's law in the form that relates current density to the electric field:

J = σE

where σ is the electrical conductivity of platinum, σ = 1.0 × 10⁷ S/m (S = 1/Ω), and E is the electric field.

Rearranging for the electric field, we get:

E = J / σ

Substituting the values, we get:

E = (3 × 10⁵ A/m²) / (1.0 × 10⁷ S/m) = 3 × 10⁻² V/m

Therefore, the strength of the very small electric field required to drive the current through the wire is 0.03 V/m.

An initially uncharged 3.67 μF capacitor and a 8.01 k Ω resistor are connected in series to a 1.50 V battery that has negligible internal resistance. What is the initial current in the circuit, expressed in milliamperes?

Answers

Answer:

Explanation:

Given an RC series circuit

Initially uncharged capacitor

C=3.67 μF

Resistor R=8.01 k Ω=8010 ohms

Battery EMF(V)=1.5V with negligible internal resistance.

The initial current in the circuit?

At the beginning the capacitor is uncharged and it has a 0V, so all the voltage appears at the resistor,

Now using ohms law

V=iR.

i=V/R

i=1.5/8010

i=0.000187A

1mA=10^-3A

Therefore, 1A = 1000mA

i=0.187 milliamps

The initial current in the circuit is 0.187 mA

Answer:

The initial current is 0.0187 mA.

Explanation:

Given that

capacitance is given as 3.67 x 10⁻⁶ F

resistance is given as 8010 Ω

voltage across the circuit is 1.5 V

Since the capacitor is initially uncharged, the capacitive reactance is zero.

From ohms law;

Voltage across the circuit is directly proportional to the opposition to the flow of current.

In these circumstances, as the battery only "sees"a resistor, the initial current can be found applying Ohm's law to the resistor, as follows:

[tex]V = I_{0}*R \\\\ I_{0} = \frac{V}{R} = \frac{1.50V}{8.011e3\Omega}\\ = 0.0187 mA[/tex]

The initial current (that will be diminishing as the capacitor charges), is 0.0187 mA.

A laboratory dish, 20 cm in diameter, is half filled with water. One at a time, 0.49 μL drops of oil from a micropipette are dropped onto the surface of the water, where they spread out into a uniform thin film. After the first drop is added, the intensity of 640 nm light reflected from the surface is very low. As more drops are added, the reflected intensity increases, then decreases again to a minimum after a total of 13 drops have been added. What is the index of refraction of the oil?

Answers

Explanation:

Formula for path difference is as follows.

             x = 2tn

and,     refractive index (n) = [tex]\frac{\lambda}{2t}[/tex]

Thickness is calculated as follows.

           Thickness (t) = [tex]\frac{volume}{area}[/tex]

       Area = [tex]\pi r^{2}[/tex]

                = [tex]\pi \times (\frac{d}{2})^{2}[/tex]

                = [tex]\frac{0.49 \times 10^{-6}}{3.14 \times 0.01 m}[/tex]

                = [tex]1.56 \times 10^{-8}[/tex] m

Now, the refractive index will be calculated as follows.

For drop,      n = [tex]\frac{\lambda}{2t}[/tex]

For B drop,    n = [tex]\frac{\lambda}{26t}[/tex]

So,     n = [tex]\frac{640 \times 10^{-9}}{26 \times 1.56 \times 10^{-8}}[/tex]

            = [tex]\frac{640 \times 10^{-9}}{40.56 \times 10^{-8}}[/tex]

            = 1.5

Thus, we can conclude that index of refraction of the oil is 1.5.

Determine the minimum work per unit of heat transfer from the source reservoir that is required to drive a heat pump with thermal energy reservoirs at 460 K and 540 K.

Answers

Answer:

The minimum work per unit heat transfer will be 0.15.

Explanation:

We know the for a heat pump the coefficient of performance ([tex]C_{HP}[/tex]) is given by

[tex]C_{HP} = \dfrac{Q_{H}}{W_{in}}[/tex]

where, [tex]Q_{H}[/tex] is the magnitude of heat transfer between cyclic device and    high-temperature medium at temperature [tex]T_{H}[/tex] and [tex]W_{in}[/tex] is the required input and is given by [tex]W_{in} = Q_{H} - Q_{L}[/tex], [tex]Q_{L}[/tex] being magnitude of heat transfer between cyclic device and low-temperature [tex]T_{L}[/tex]. Therefore, from above equation we can write,

[tex]&& \dfrac{Q_{H}}{W_{in}} = \dfrac{Q_{H}}{Q_{H} - Q_{L}} = \dfrac{1}{1 - \dfrac{Q_{L}}{Q_{H}}} = \dfrac{1}{1 - \dfrac{T_{L}}{T_{H}}}[/tex]

Given, [tex]T_{L} = 460 K[/tex] and [tex]T_{H} = 540 K[/tex]. So,  the minimum work per unit heat transfer is given by

[tex]\dfrac{W_{in}}{Q_{H}} = \dfrac{T_{H} - T_{L}}{T_{H}} = \dfrac{540 - 460}{540} = 0.15[/tex]

Final answer:

The minimum work required to operate a heat pump between two thermal reservoirs at 460 K and 540 K is determined using the performance coefficient equation, Kp = Qh/W = Th/(Th – Tc). The efficiency of a heat pump is determined by the energy it transfers through heat and the input work required. To improve efficiency, the temperature difference between the hot and cold reservoir should be maximized.

Explanation:

The question pertains to the work-power balance in a heat pump operating between two thermal reservoirs. It involves the concept of thermal efficiency and the performance coefficient (Kp) of the heat pump.

Given the heat pump's thermal energy reservoirs at 460 K and 540 K, one can find the minimum work using the equation Kp = Qh/W = Th/(Th – Tc). Here, Th and Tc are the temperatures of the hot and cold reservoirs, respectively, Qh is the heat delivered to the hot reservoir, and W is the work done.

Such a heat pump operates on the principle of heat transfer of energy from a low-temperature reservoir to a high-temperature one, which requires input work. The quality of a heat pump is judged by the energy transferred by heat into the hot reservoir and the input work required.

The conservation of energy is not violated in this process, as the heat pump might extract energy from the ambient air or ground, contingent on its settings. Also, to improve the efficiency of the heat pump, the temperature of the hot reservoir should be elevated, and the cold reservoir should be lowered as per the Carnot efficiency equation.

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What is the magnitude of the electric field at a distance 60 cm from the center of the sphere? The radius of the sphere 30 cm, the charge on the sphere is 1.56 × 10−5 C and the permittivity of a vacuum is 8.8542 × 10−12 C 2 /N · m2 . Answer in units of N/C.

Answers

Answer

[tex]3.9*10^{5}N/C[/tex]

Explanation:

from the expression for determing the magnetic field strength

[tex]E=\frac{q}{4\pi e_{0}d^2 }\\[/tex]

since the charge is given as

[tex]q=1.56*10^{-5}c\\[/tex]

and the distance is

d=60cm=0.6m

We can calculate the constant k

[tex]K=\frac{1}{4\pi e_{0}}\\ K=\frac{1}{4\pi *8.8542*10^{-12}}\\k=8.98*10^{9}\\[/tex]

if we substitute values, we arrive at

[tex]E=\frac{8.98*10^9 *1.56*10^{-5}}{0.6^2} \\E=389133.33\\E=3.9*10^{5}N/C[/tex]

Explanation:

Below is an attachment containing the solution.

URGENTLY NEED HELP WITH PHYSICS?

A vaulter is holding a horizontal 3.00-kg pole, 4.50 m long. His front arm lifts straight up on the pole, 0.750 from the end, and his back arm pushes straight down on the end of the pole. How much force does his back arm exert on the pole?

(Unit= N)

NEED HELP FAST

Answers

Answer:

58.8 N

Explanation:

Let 'F₁' be the force by front arm and 'F₂' be the force by back arm.

Given:

Mass of the rod (m) = 3.00 kg

Length of the pole (L) = 4.50 m

Acceleration due to gravity (g) = 9.8 m/s²

Distance of 'F₁' from one end of pole (d₁) = 0.750 m

'F₂' acts on the end. So, distance between 'F₁' and 'F₂' = 0.750 m

Now, weight of the pole acts at the center of pole.

Now, distance of center of pole from 'F₁' is given as:

d₂ = (L ÷ 2) - d₁

[tex]d_2=\frac{4.50}{2}-0.75=1.5\ m[/tex]

Now, as the pole is held horizontally straight, the moment about the point of application of force 'F₁' is zero for equilibrium of the pole.

So, Anticlockwise moment  = clockwise moment

[tex]F_2\times d_1=mg\times d_2\\\\F_2=\frac{mg\times d_2}{d_1}[/tex]

Plug in the given values and solve for 'F₂'. This gives,

[tex]F_2=\frac{3.00\ kg\times 9.8\ m/s^2\times 1.5\ m}{0.75\ m}\\\\F_2=\frac{44.1}{0.75}=58.8\ N[/tex]

Therefore, the force exerted by the back arm on the pole is 58.8 N vertically down.

                                                                         

Point charges of 4.75 µC and −1.50 µC are placed 0.350 m apart. (Assume the negative charge is located to the right of the positive charge. Include the sign of the value in your answers.)

(a) Where can a third charge be placed so that the net force on it is zero?
_______ m to the right of the −1.50 µC charge
(b) What if both charges are positive?

_______ m to the right of the 1.50 µC charge

Answers

Answer:

Explanation:

Let the position of balance point be x distance from 1.5 µC on the right side . Balance point can not be on the left side or between the charges because in that case electric field by both the charges will be in the same direction .

For equilibrium of field

k x 4.75 µC / ( .35 +x )² -  k x  1.5  µC / x ² = 0

4.75 / ( .35 +x )² = 1.5 / x²

( .35 +x )² / x² = 4.75 / 1.5

( .35 +x )² / x² = 3.167

( .35 +x ) / x =  1.78

.35 + x = 1.78 x

.78 x = .35

x = .45 m ( + ve ) to the right of 1.50  µC

b ) When both the charges are positive , balance point will lie in between them because , electric field will be in opposite direction .

For equilibrium of field

k x 4.75 µC / ( .35 - x )² =   k x  1.5  µC / x ²

4.75 / ( .35 -x )² = 1.5 / x²

( .35 -x )² / x² = 4.75 / 1.5

( .35 -x )² / x² = 3.167

( .35 -x ) / x =  1.78

.35 -x = 1.78 x

2.78 x = .35

x = .126 m  ( - ve ) to the right of 1.50  µC

Reasons for which petroleum is the chosen fuel for transportation in the U.S. include
1) its energy value per unit volume
2) its ability to quickly start or stop providing energy
3) its low amount of pollution produced per joule

Answers

Answer:

The Reasons for which petroleum is the chosen fuel for transportation in the U.S. include number 1) and 2).

Explanation:

The main reasons why oil is the most used fuel in the USA is because of its energy potential with a high combustion power and a better octane rating compared to other fuels. Thus, fossil fuel derived from oil has a high energy value per unit volume and an ability to quickly start or stop providing energy.

What pressure gradient along the streamline, dp/ds, is required to accelerate air at standard temperature and pressure in a horizontal pipe at a rate of 274 ft/s2?

Answers

Answer:

The answer to this question is attached.

Final answer:

The pressure gradient required to accelerate the air inside a pipe can be calculated using Euler's simplified equation for fluid motion. At standard temperature and pressure, you would need a pressure gradient of approximately -102.3 Pa/m to accelerate air at 274 ft/s².

Explanation:

To calculate the pressure gradient, or dp/ds, required to accelerate the air inside a pipe, we can use Euler's equation for fluid motion, which in its simplified form is dp/ds = -ρa, where ρ represents the density of the fluid (in this case, air) and a is the acceleration. For standard temperature and pressure, the density of the air is approximately 1.225 kg/m³. It is important to note that the acceleration provided is in feet per second squared, so we would need to convert that to meters per second squared to match units with the density. The conversion factor is 1 ft/s² = 0.3048 m/s², resulting in an acceleration of approximately 83.515 m/s². By substituting these values into the equation, we get dp/ds = -(1.225 kg/m³)(83.515 m/s²) = -102.3 kg/(m·s²), or -102.3 Pa/m, since a Pascal (Pa) is equivalent to a kg/(m·s²).

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The GPS (Global Positioning System) satellites are approximately 5.18 mm across and transmit two low-power signals, one of which is at 1575.42 MHz (in the UHF band). In a series of laboratory tests on the satellite, you put two 1575.42 MHz UHF transmitters at opposite ends of the satellite. These broadcast in phase uniformly in all directions. You measure the intensity at points on a circle that is several hundred meters in radius and centered on the satellite. You measure angles on this circle relative to a point that lies along the centerline of the satellite (that is, the perpendicular bisector of a line which extends from one transmitter to the other). At this point on the circle, the measured intensity is 2.00 W/m^2.

Required:
What is the intensity at a point on the circle at an angle of 4.45° from the centerline?

Answers

Answer:

intensity at a point on the circle at an angle of 4.45° from the center line is 1.77 W/m².

Explanation:

See attached picture.

The intensity at a point on the circle at an angle of 4.45° from the centerline is approximately 4.00 W/m².

To find the intensity at a point on the circle at an angle of 4.45° from the centerline, we need to consider the interference pattern created by the two transmitters.

1. Wavelength Calculation:

The wavelength [tex](\(\lambda\))[/tex] of the transmitted signal can be calculated using the frequency [tex](\(f\))[/tex] and the speed of light c.

[tex]\[ \lambda = \frac{c}{f} \][/tex]

Given:

- [tex]\( c = 3 \times 10^8 \)[/tex] m/s (speed of light)

- [tex]\( f = 1575.42 \times 10^6 \)[/tex] Hz (frequency)

[tex]\[ \lambda = \frac{3 \times 10^8}{1575.42 \times 10^6} \approx 0.1902 \text{ meters} \][/tex]

2. Phase Difference Calculation:

The phase difference [tex](\(\Delta \phi\))[/tex] between the two waves at a point on the circle is determined by the path difference [tex](\(\Delta L\))[/tex] travelled by the waves.

The path difference is given by:

[tex]\[ \Delta L = d \sin(\theta) \][/tex]

where:

- d is the distance between the two transmitters (5.18 mm = 0.00518 m)

- [tex]\(\theta\)[/tex] is the angle from the centerline (4.45°)

[tex]\[ \Delta L = 0.00518 \sin(4.45^\circ) \approx 0.00518 \sin(0.0776) \approx 0.00518 \times 0.0775 \approx 0.0004019 \text{ meters} \][/tex]

The phase difference is:

[tex]\[ \Delta \phi = \frac{2 \pi \Delta L}{\lambda} = \frac{2 \pi \times 0.0004019}{0.1902} \approx 0.0133 \text{ radians} \][/tex]

3. Intensity Calculation:

The intensity at a given point due to two sources interfering constructively or destructively can be found using:

[tex]\[ I = I_0 \left(1 + \cos(\Delta \phi)\right) \][/tex]

Here, [tex]\(I_0\)[/tex] is the intensity when both waves interfere constructively at the centerline [tex](\(\theta = 0^\circ\))[/tex], which is given as 2.00 W/m^2.

[tex]\[ I = 2.00 \left(1 + \cos(0.0133)\right) \][/tex]

Since [tex]\(\cos(0.0133) \approx 0.9999\)[/tex]:

[tex]\(\cos(0.0133) \approx 0.9999\)[/tex]

Thus, the intensity at a point on the circle at an angle of 4.45° from the centerline is approximately 4.00 W/m².

A short circuit is a circuit containing a path of very low resistance in parallel with some other part of the circuit. Discuss the effect of a short circuit on the portion of the circuit it parallels. Use a lamp with a frayed line cord as an example.

Answers

Answer:

note:

please find the attachment

Explanation:

A frayed cord means that the insulation of the cord is worn out which exposes the cord and when it touches any other conductor a short circuit happens which is basically the flow of very high amount of current.

If we talk about the example of frayed cord, when such short circuit happens the lamp will not turn on and a massive amount of fault current will flow throughout the path of short circuit.

Now what happens?

There are two possibilities;

If there exists a circuit breaker, then no substantial amount of damage would be done since the circuit breaker will trip itself and open the circuit that eventually halts the fault current.If there is no circuit breaker, then this massive fault current will keep on accumulating that causes excessive heating of the conductors and also producing sparks which most probably would end up in a fire hazard.

calorimeter has aluminum inner cup of mass 120 gram containing 100 ml water at temperature 20 degree Celsius. Brass piece with mass 100 gram is heated to 100 degree Celsius, and then immersed in the calorimeter. Calculate the final temperature of the system. The specific heat of brass is 0.09 cal/(gramXdeg.C) . The additional necessary data are provided in the text.

Answers

Answer:

the final temperature of the system of the system is 25.32°C

Explanation:

We are not given specific capacity of water and aluminium, so we use their standard values, also we are not given the density if water so we assume the standard vale of density of water

The aluminium calorimeter has a mass Mc= 120g

Volume of water in calorimeter = 100ml at θc =20°C

Density of water is

1000Kg/m³ = 1g/mL

Then, density = mass/ volume

Mass=density ×volume

Mass=1g/mL×100mL

Mass=100gram

Then, the mass of water is

Mw = 100gram

Mass of brass is Mb = 100gram

The temperature of brass is θb=100°C

The specific heat capacity of water is Cw= 1cal/g°C

The specific heat capacity of aluminum Ca=0.22cal/g°C

We are looking for final temperature θf=?

Given that the specific heat capacity of brass is Cb=0.09Cal/g°C

Using the principle of calorimeter;

The principle of calorimetry states that if there is no loss of heat in surrounding the total heat loss by hot body equals to total heat gained by a cold body.

So, the calorimeter gained heat and the liquid in the calorimeter gain heat too

Heat gain by calorimeter(Hc) = Mc•Ca•∆θ

Where Mc is mass of calorimeter,

Ca is Specific Heat capacity of Calorimeter

∆θ=(θf-θc)

Hc=Mc•Ca•∆θ

Hc=120•0.22•(θf-20)

Hc=26.4(θf-20)

Hc=26.4θf-528

Also, heat gain by the water

Heat gain by wayer(Hw) = Mw•Cw•∆θ

Where Mw is mass of water,

Cw is Specific Heat capacity of water

∆θ=(θf-θw),

Note that the temperature of the water and the calorimeter are the same at the beginning i.e. θc=θw=20°C

Hw=Mw•Cw•∆θ

Hw=100•1•(θf-20)

Hw=100(θf-20)

Hw=100θf-2000

Also heat loss by the brass is given by

heat loss by brass

Heat loss by brass(Hb)= Mb•Cb•∆θ

Where Mb is mass of brass,

Cb is Specific Heat capacity of brass

∆θ=(θb-θf)

Therefore,

Hb=Mb•Cb•∆θ

Hb=100•0.09•(100-θf)

Hb=9(100-θf)

Hb=900-9θf

Applying the principle of calorimeter

Heat gain = Heat loss

Hc+Hw=Hb

26.4θf-528 + 100θf-2000=900-9θf

26.4θf+100θf+9θf=900+2000+528

135.4θf=3428

Then, θf=3428/133.4

θf=25.32°C

The final temperature of the system is 25.32 degree Celsius.

Given data:

The mass of aluminum cup is, m = 120 g .

The mass of brass piece is, m' = 100 g.

The volume of water in aluminum cup is, V = 100 ml.

The temperature of water is, T = 20 degree Celsius.

The specific heat of brass is, [tex]c''=0.09 \;\rm cal/g ^\circ C[/tex].

The temperature of brass is, T'' = 100 degree Celsius.

The principle of calorimetry states that if there is no loss of heat in surrounding the total heat loss by hot body equals to total heat gained by a cold body.

So, first calculate heat gain by calorimeter,

H = mc (T' - T)

Here, c is the specific heat of aluminum and its value is, [tex]0.22 \;\rm cal/g^\circ C[/tex]. Solving as,

[tex]H = 120 \times 0.22 (T' - 20)\\H = 26.4T' - 528[/tex]

And, heat gain by water is,

[tex]H'=m'c'(T'-T)[/tex]

Here, c' is the specific heat of water. ( c' =1 )

Solving as,

[tex]H'=100 \times 1 \times (T'-20)\\H' = 100T' -2000[/tex]

Now, heat loss by brass is,

[tex]H'' = m'c'' (T''-T')\\\\H'' = 100 \times 0.09 \times (100-T')\\\\H'' = 900-9T'[/tex]

Applying the principle of calorimeter

Heat gain = Heat loss

H + H' = H''

(26.4T' - 528) + (100T' - 2000) = (900 - 9T')

135.4 T' = 3428

T ' = 25.32 degree Celsius

Thus, we can conclude that the final temperature of the system is 25.32 degree Celsius.

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What is the ideal banking angle (in degrees) for a gentle turn of 1.75 km radius on a highway with a 120 km/h speed limit (about 75 mi/h), assuming everyone travels at the limit?

Answers

Answer:

Ф = 4.98 °

Explanation:

Given:

R = 1.75 km = 1.75 * 10^3

g = 9.8 m/s^2

v = 120 km/h ==> 33.33 m/s

required:

Ф

solution:

The angle(Ф) is given by

Ф = arctan(v^2/R*g)

   = arctan(33.33^2/9.8*1.75 * 10^3)

   = 4.98 °

note:

there maybe error in calculation but method is correct.

You are a member of a citizen's committee investigating safety in the high school sports program. You are interested in knee damage to athletes participating in the long jump (sometimes called the broad jump). The coach has her best long jumper demonstrate the event for you. He runs down the track and, at the take-off point, jumps into the air at an angle of 30 degrees from the horizontal. He comes down in a sand pit at the same level as the track 26 feet away from his take-off point. With what velocity (both magnitude and direction) did he hit the ground?

Answers

Final answer:

The velocity at which the long jumper landed can be computed by separating the jump into horizontal and vertical components, using the initial take-off angle and the horizontal distance. The horizontal and vertical velocities are combined to find the magnitude of the total landing velocity, and the arctangent of their ratio gives the direction.

Explanation:

To determine the velocity at which the long jumper landed, we need to consider the projectile motion of the jump. There are two components of velocity to consider: the horizontal (vx) and the vertical (vy) at the point of landing.

First, the horizontal velocity (vx) can be found by dividing the total horizontal distance by the time of flight (t). The equation of horizontal motion is:

vx = d / t, where d is the horizontal distance.

The vertical velocity (vy) of the jumper when he lands will be the same magnitude but opposite in direction to the vertical velocity at take-off due to symmetry in projectile motion, assuming no air resistance. The vertical velocity at take-off can be calculated using the initial jump angle (Ө) and the initial velocity (v0).

Using the initial angle of 30°, the vertical component of the initial velocity at take-off (v0y) is:

v0y = v0 * sin(Ө).

Since the vertical motion is subject only to acceleration due to gravity (g), the final vertical velocity at landing (vy) will be v0y (but in the opposite direction).

The total landing velocity (v) is then found by combining these two components using the Pythagorean theorem:

v = √(vx^2 + vy^2).

The direction of the landing velocity is given by the angle made with the horizontal, found using the arctangent of the ratio of vy over vx:

θ = arctan(vy / vx).

These calculations would provide the magnitude and direction of the landing velocity.

A piston–cylinder assembly contains 5.0 kg of air, initially at 2.0 bar, 30 oF. The air undergoes a process to a state where the pressure is 1.0 bar, during which the pressure–volume relationship is pV = constant. Assume ideal gas behavior for the air. Determine the work and heat transfer, in kJ.

Answers

Answer:

The work and heat transfer for this process is = 270.588 kJ

Explanation:

Take properties of air from an ideal gas table.  R = 0.287 kJ/kg-k

The Pressure-Volume relation is PV = C

T = C for isothermal process

Calculating for the work done in isothermal process

W = PV₁ [tex]ln[\frac{P_{1} }{P_{2} }][/tex]

   = mRT₁[tex]ln[\frac{P_{1} }{P_{2} }][/tex]      [∵pV = mRT]

   = (5) (0.287) (272.039) [tex]ln[\frac{2.0}{1.0}][/tex]

   = 270.588 kJ

Since the process is isothermal, Internal energy change is zero

ΔU = [tex]mc_{v}(T_{2} - T_{1} ) = 0[/tex]

From 1st law of thermodynamics

Q = ΔU  + W

   = 0 + 270.588

   = 270.588 kJ

To find the work and heat transfer in this process, we can apply the First Law of Thermodynamics. We can determine the work done using the equation pV = constant and calculate the heat transfer using the equation Q = CpdT.

To find the work and heat transfer in this process, we need to apply the First Law of Thermodynamics. The First Law states that the change in internal energy of a system is equal to the heat transfer into the system minus the work done by the system. In this case, since the process is isobaric (constant pressure), we can determine the work done by integrating the equation pV = constant. This will give us the equation W = p(Vf - Vi), where W is the work done, p is the pressure, and Vf and Vi are the final and initial volumes respectively.

Since the process is isobaric, the heat transfer can be calculated using the equation Q = CpdT, where Q is the heat transfer, Cp is the specific heat at constant pressure, and dT is the change in temperature. In this case, since the temperature change is not given explicitly, we can assume it to be the same as the change in internal energy, which gives us dT = dU/Cp.

By substituting the given values into the equations, we can calculate the work and heat transfer.

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Question 1 (2 points)What change, if any, is needed in sentence 1?Question 1 options:A change Bobby to bobbyB change a to anC change the period to a question markD make no changeQuestion 2 (2 points)What change, if any, is needed in sentence 4?Question 2 options:A change to to tooB change there to they'reC change Bobby's to BobbysD change doesnt to doesn'tQuestion 3 (2 points)What change, if any, should be made in sentence 6?Question 3 options:A change He's to HisB change a to anC change persson to personD make no changeQuestion 4 (2 points)What change should be made in sentence 8?Question 4 options:A delete the comma after blindB change resist to ressistC change to to twoD no change neededQuestion 5 (2 points)What change, if any, is needed in sentence 10?Question 5 options:A insert a comma after familyB change knows to knewC change the period to a question markD no change needed In a game of baseball, a player hits a high fly ball to the outfield. (a) Is there a point during the flight of the ball where its velocity is parallel to its acceleration? (b) Is there a point where the balls velocity is perpendicular to its acceleration? Explain in each case. With any installation, remember the importance of using a ground strap (ground bracelet) to ground yourself when working inside a computer case to protect components against ____. The man on the far left of this photograph is acandidate for office.Which impressions is this photo seeking to convey?Check all that apply.He knows how to improve the economy.He understands the needs of working Americans.He has political experienceHe is a hard worker.He wants to support the community. please help me I really need to finish this asap!! A Diesel cycle engine is analyzed using the air standard method. Given the conditions at state 1, compression ratio (r), and cutoff ratio (rc) determine the efficiency and other values listed below.Note: The gas constant for air is R=0.287 kJ/kg-K.--Given Values--T1 (K) = 306P1 (kPa) = 140r = 10rc = 1.75a) Determine the specific internal energy (kJ/kg) at state 1. Your Answer =b) Determine the relative specific volume at state 1. Your Answer =c) Determine the relative specific volume at state 2. Your Answer =d) Determine the temperature (K) at state 2. Your Answer =e) Determine the pressure (kPa) at state 2. Your Answer =f) Determine the specific enthalpy (kJ/kg) at state 2. Your Answer =g) Determine the temperature (K) at state 3. Your Answer =h) Determine the pressure (kPa) at state 3. Your Answer =i) Determine the specific enthalpy (kJ/kg) at state 3. Your Answer =j) Determine the relative specific volume at state 3. Your Answer =k) Determine the relative specific volume at state 4. Your Answer =l) Determine the temperature (K) at state 4. Your Answer =m) Determine the pressure (kPa) at state 4. Your Answer =n) Determine the specific internal energy (kJ/kg) at state 4. Your Answer =o) Determine the net work per cycle (kJ/kg) of the engine. Your Answer =p) Determine the heat addition per cycle (kJ/kg) of the engine. Your Answer =q) Determine the efficiency (%) of the engine. Your Answer =help A through Q [The following information applies to the questions displayed below.] Raner, Harris & Chan is a consulting firm that specializes in information systems for medical and dental clinics. The firm has two officesone in Chicago and one in Minneapolis. The firm classifies the direct costs of consulting jobs as variable costs. A contribution format segmented income statement for the companys most recent year is given: Office Total Company Chicago Minneapolis Sales $ 450,000 100.0 % $ 90,000 100 % $ 360,000 100 % Variable expenses 243,000 54.0 % 27,000 30 % 216,000 60 % Contribution margin 207,000 46.0 % 63,000 70 % 144,000 40 % Traceable fixed expenses 100,800 22.4 % 46,800 52 % 54,000 15 % Office segment margin 106,200 23.6 % $ 16,200 18 % $ 90,000 25 % Common fixed expenses not traceable to offices 72,000 16.0 % Net operating income $ 34,200 7.6 % Required: 1-a. Compute the companywide break-even point in dollar sales. 1-b. Compute the break-even point for the Chicago office and for the Minneapolis office. 1-c. Is the companywide break-even point greater than, less than, or equal to the sum of the Chicago and Minneapolis break-even points?